I am wondering how the factory "adjusts" their screens prior to shipping.. is there a potentiometer on the back that you adjust with a very fine screwdriver affecting the charge and hence the contrast?

Sony uses a potentiometer on their mainboard to adjust the Vcom (common voltage) setting. This is an additional voltage that must be applied to the display to compensate for a residual charge on the glass caused by addressing the display. The value for this is determined in the display factory and printed on it. During assembly they must adjust this setting manually.

However, adjusting the setting of the potentiometer yourself will only result in worse screen performance. You might be able to make black more black, but then your white will become darker.

The visual performance of the display is mainly determined by the quality of the E-ink material.

Sony uses a potentiometer on their mainboard to adjust the Vcom (common voltage) setting. This is an additional voltage that must be applied to the display to compensate for a residual charge on the glass caused by addressing the display. The value for this is determined in the display factory and printed on it. During assembly they must adjust this setting manually.

However, adjusting the setting of the potentiometer yourself will only result in worse screen performance. You might be able to make black more black, but then your white will become darker.

The visual performance of the display is mainly determined by the quality of the E-ink material.

PVI, Prime View International, in Taiwan, is very close to owning the E-Ink technology very soon, I think the contract will be signed this month between CEO Scott Liu in Taiwan and the E-Ink people in Boston. One thing I found in researching PVI is that it is part of an old Taiwan paper company called The Yuen Fong Yu Group, that started ops in 1935 during the Japanese occupation of Taiwan island (1895-1945). The founders were Taiwanese and the owners still are. Yuen Fong Yu means "Forever Wealth Remnants" in a loose translation of the three Mandarin words, and the company name might mean something like "Remnants of Infinite Prosperity." E-Ink will be in good hands in Taiwan, and PVI looks poised to hit the bigtime globally, since 90 percent of all e-readers use the E-Ink technology.

The parent company used to make toilet paper, and still does I believe. If you google the parent name "Yuen Fong Yu Group" you can see their website in English and Chinese.